2003-01-07_REVISION - M1974069 (2)

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~~ EX131BIT D -MINING PLAN The remaining extraction azea is divided into 3 proposed cells; 6 & 7 combined, 8, and 9. Mining of cells 6&7 will be complete in 7nauary of 2003, at which time mining in cell 9 will commence, with cell 8 being the last cell to be mined. The mining of each cell will begin with the removal of topsoil and overburden, which will be stored separately in the storage aeeas noted on the photomap. The test hole logs prepared by Hogan and Ohlhansen indicate the overburden soils in the area of pit numbers 8 & 9 consist of a dark brown clayey-sandy soil and the depth of this overburden ranges from 30 inches to 50 inches. The depth of the gravel in this azea ranges from 8 feet to 12 feet followed by gray claystone / shalestone. The borings in the azea that inchrdes cells 8 and 9 indicate the area nearest the Big Barnes Ditch may have overburden ranging for 30 to 50 inches in depth. Closer to the River, the overburden depth may range from 24 to 36 inches. The boring logs of the azea indicate that the sand and gravel layer ranges from 11 feet near the Big Barnes Ditch to 8 feet closer to the river. The overburden soils in the azea of pits 8 and 9 have been supporting alfalfa and native hay for many years. For more detailed soils information see Exhibit I. Overburden will be removed with scrapers and/or excavators and trucks and the gravel removal will be with an excavator and trucks. A 20 horsepower, six-inch pump will be used for dewatering of pits 8 and 9. The dischazge water will be pumped into existing pond 2 with an overflow pipe into the existing pond East of pond 2 and will exfiltrate into the ground water through the gravel banks of the ponds. No water will return directly to the Big Thompson River so no dischazge permit is required. All water from dewatering of proposed pits 8 and 9 will be pumped into the existing ponds. Approximately 1700 gpm of water is pumped from a prior pond for washing and is returned to the existing settling ponds near the office and equipment area. No water from the washing operation is discharged into the river. Mined material will be hauled by truck to the existing crushing, washing, and sizing plant by way of the haul roads noted on the Mining Plan (Exhibit C). The 26.8 acres which includes the existing stockpile, crusher, batch plant, equipment storage and office area has been included as part of the total affected azea. Truck crossing signs will be used on County Road 19E when the haul road crossing is in use. If the deposit of mud and dirt on any connecting improved roads becomes excessive, it will be removed. The extraction areas will be surface wet pits; therefore, it should not be necessary to water down any active areas other than haul roads for dust control. It is estimated that 150,000 to 200,000 tons of sand and gravel will be extracted each year to complete the operation, including reclamation within twelve years. Final grading and seeding as part of the reclamation plan will be completed within the last six to twelve months, unless weather conditions prohibit entry into the area. There aze approximately 35 acres of extractable azea, which means 3 to 4 acres of surface area will be mined each yeaz for completion in twelve years. On this basis, the following schedule approximates the months and yeazs in which